This invention relates to intelligent networks and more particularly to a method and system to access applications operating in the so-called Service Control Points (SCP) and Intelligent Peripherals (IP) of the public switching systems.
In the telephone networks provided by the carriers, call routing and call processing were originally handled by public switching systems also called Central eXchanges (CX). Today, in the intelligent network architecture, the CXs still handle call routing but call processing and other features, forming the enhanced services offering of the carriers, are handled by intelligent network components which are satellites of the CXs. These intelligent components such as Service Control Points (SCP) and Intelligent Peripherals (IP) are real time computers running applications so called Service Logic Programs (SLP), and communicating with the CXs according to protocols which are generally standardized.
SLP applications for translation of phone call numbers, caller filtering etc. are running in the SCPs. Phone call number translation is simple when based on routing tables and handled by CXs. Call number translation handled by the SLPs is more complex. For example, for free 800 call numbers, the real call number depends on the date and time (rerouting to back up sites is performed during weekends or nights, for instance) or the call number origin location (the call maybe rerouted to the nearest site of the calling number). The SLPs running in IPs support voice interact with the caller for playing announcement to the calling party or prompting and collecting User Information from the calling party.
Intelligent network architectures are generally standardized. The Intelligent Network (IN) standard defined by the ITU-T comprises CS-1 (Q.121x family of Recommendations) and CS-2(Q.122x family of Recommendations); the Advanced Intelligent Network (AIN) standard is defined by Bellcore and the Wireless Intelligent Network (WIN) defines an extension of the TIA/EIA IS-41 Mobile Network Architecture for Mobile telephones. These three standards, ITU, AIN and WIN define, for instance, where to store the subscriber information; they define, more particularly, the communication between the CXs and the SCPs or IPs by specifying the characteristics of the network session, transport session and presentation layers of the OSI model.
Each SLP interfacing the presentation layer should be adapted to the standard it supports. This means that a SLP operating in an SCP or an IP compatible with Bellcore standards cannot be used in an SCP or IP compatible with ITU standards, or with WIN standards, and must be reworked when ported from an environment to the other. This is a problem for developers of networking software or integrated solution providers.
In addition, within the ITU and the Bellcore standards, there are two different sets of flow exchanges between the SCP and the IP which are either the direct connection mode or the relay mode through the Cx. The sequence of requests and responses which must be exchanged (and therefore transmitted from or received by the SLP) is different from one mode to the other and different for each of the standards (ITU or Bellcore, respectively).
If nothing is done to solve this problem, each SLP my need up to five different versions, depending upon the standard and the mode of connection. The first version follows the Bellcore standard and implements the direct connection mode so called xe2x80x98SR-3511xe2x80x99. The second version follows the Bellcore standard but implements the relay mode so called xe2x80x98GR-1129xe2x80x99. The third version follows the ITU standard and implements the direct mode so called xe2x80x98ETSI CoreInap, direct connection configurationxe2x80x99. The fourth version of SLP follows the ITU standard and implements the relay mode so called ETSI Corelnap, relay configuration. When using the WIN(EIA/TIA) standard, a fifth version of SLP is necessary because although the semantics of the SCP-IP communication verbs are similar for wireline and wireless networks, the formats and protocols are different.
One of the objects of the invention is to enable the SLP programs to be executed in network equipment implementing any protocol of communication used in intelligent networks and any type of connection mode.
In brief, this and other objects are achieved by insulating the applications operating on the intelligent network components (the SLP) from the protocol exchanges with an independent application program interface, which hides the differences in syntax and in exchange flows, from the applications.
One of the advantages of the invention is to reduce development and maintenance costs of porting SLPs from one intelligent network environment to one other.